Fluid Mechanics and Hydraulic Machines (Book with DVD)

Fluid mechanics is a branch of physics which concerns the study of  uids and the ways in which they interact with forces. Both liquids and gases are considered to be  uids for the purposes of this branch of science. Often, the  eld of  fluid mechanics is divided into two more speci c  elds of study. These are  fluid statics and  uid dynamics, which concern fluids at rest and  fluids in motion, respectively. Fluid mechanics can involve highly complex mathematics, and the aid of modern computers has enhanced this science signi cantly. Fluid mechanics is typically de ned as having three basic premises or assumptions at its root. The  rst is the conservation of mass, which means that mass can neither be instinctively created nor destroyed, although it may change forms. The second assumption, the conservation of momentum, is somewhat similar.

This law states that the total momentum in a closed system is constant, and cannot spontaneously appear or disappear. The third basic assumption governing  fluid mechanics is what is known as the continuum hypothesis. This is a way of seeing  uids that does not take into account the presence of discrete molecules. Hydraulic machines are machinery and tools that use liquid  uid power to do simple work. Heavy equipment is a common example. In this type of machine, hydraulic fluid is transmitted throughout the machine to various hydraulic motors and hydraulic cylinders and becomes pressurized according to the resistance present.